Targeting good user experiences, softness and stretchability are essential features for epidermal devices in body signal monitoring and body area stimulation. A highly soft, stretchable and sticky polydimethylsiloxane based elastomer (S3-PDMS) is achieved by a simple process with a widely used siloxane precursors, the properties of which are tuned by adding small fractions of an amine-based polymer, ethoxylated polyethylenimine (EPEI). This allows formation of a thick unobstrusive patch and may ease implementation of epidermal electronics in wearable healthcare applications.